The Environmental Epidemiology Research Core's (EERC) mission is to foster the conduct of multi-disciplinary research in the EHS Center relating to environmental exposures and how such factors interrelate to lifestyle characteristics, human biological mechanisms and systems, and genetic susceptibility to affect human health and quality of life. The focus in the Core is in three disease areas: allergy and asthma, cancer, and neurological diseases. The Detroit metropolitan area is an exceptionally rich population laboratory in which to conduct such research as it is extraordinarily diverse in terms of ethnicity and culture, socioeconomic status, occupations, and environmental characteristics. Other features of this location that augment the Center?s research capacity include the ability to identify, using automated data bases, well defined and characterized study populations (e.g. members of the Health Alliance Plan, owned by Henry Ford Health System and the tenth largest HMO in the country; the population served by the Henry Ford Medical Group, approximately 25% of the Detroit area; 24,600 older individuals enrolled in the Detroit area Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial), and the presence of one of the oldest NCI designated SEER cancer registries in the nation, which has been the predominant contributor of cancer data on African Americans. The Core mission is realized both by opportunities provided to coalesce the expertise and ideas of Core members, and by members' interactions with the other EHS Center Research and Facility Core investigators. Goals of the Core are to: 1) advance the performance of multi-disciplinary and inter-institutional epidemiological research in the EHS Center, in content specific areas relevant to environmental and occupational toxicology and atopic diseases, cancer and neurological diseases; 2) foster state-of-the-art measurement of biological markers of exposure, susceptibility and disease within environmental epidemiology studies, using EHS Center core expertise; 3) Cultivate formal and informal interactions of Core members with other EHS Center members, including the Community Outreach and Education Program and EHS Facility Cores, and externally with investigators at other EHS Centers, and at NIEHS.